--- - |2 Abstract Despite extensive research on the harmful effects of peer victimization, little is known about whether prosocial treatment from peers contributes to healthy socioemotional development. To address this issue, 366 third and fourth graders (170 boys; Mage = 9.34) were followed over three time points. Children completed measures of prosocial peer treatment, peer victimization, depressive affect, and friendship quality. Teacher‐reports of depressive affect and peer‐reports of aggression, victimization, and friendships were also obtained. Controlling for peer victimization, number of friends, and friendship quality, prosocial peer treatment negatively predicted depressive affect. For boys, prosocial peer treatment mediated the association between victimization and teacher‐reported depressive affect. These findings underscore the importance of prosocial peer group treatment and the need to broaden the goals of anti‐bullying interventions to include the promotion of positive peer interactions. - Social Development, Volume 27, Issue 3, Page 619-635, August 2018.